This has been asked before but there was never an answer given. My Original LX SS Tacho starts off reading ok but after about half an hour starts to read higher and higher until it sits around 6000rpm at idle. park it up over night start up the next day all is fine for half an hour of driving then the same thing happens.
I have replaced the voltage regulator with the Jaycar DC to DC regulator and set at 5 volts, soldered a wire bridge across where the selector switch usually goes. checked all wiring and all other gauges read fine. no the needle hasnt been painted etc. checked wiring through to negative side of standard style coil. runs an old school SBC with standard distributor.
anyone have any ideas as there isn't much more I can think of.
Edited by CI 0308, 01 June 2017 - 06:00 PM.